Electric-arc lamp.



No. s7a,|42. Patented m 9, mm. W. E. svmons.

ELECTRIC ARC LAMP.

(Application filgd Feb. 15, 1901.)

2 Sheets$heet I..

(no Model.)

No. 678.l42. v Patented July 9, l90l. W. E. SYMONS.

ELECTRIC ARC LAM-P.

(Application filed Feb. 15, 1901.

2 Sheets-Sheet 2,.

(Nn Model.)

m: Norms vnzas co. PNOTO-LITHD-. wuummou. a. c.

raster VILLIAM EDWARD SYMONS, OF RI'IIVVDERIN, ENGLAND, ASSIGNOR TO NETTLEFOLDS, LIMITED, OF BIRMINGHAM, ENGLAND.

I ELECTR|C=ARC LAMP.

SPEGIFIOATION forming part of Letters Patent No. 67 8,142, dated July 9, 1901.

Application filed February 15, 1901. Serial No. 47,506, (1510 model.)

To all whom it may concern:

Be it known that 1, WILLIAM EDWARD SY- MONS, a subject of the King of Great Britain, residing at Rhiwderin, near Newport, in the county of Monmouth-England, have invented certain new and useful Improvements in Electrical-Arc Lamps, of which the following is a specification.

My invention consists in constructing and arranging in the manner hereinafter described the parts of an electrical-arc lamp, the object of the said invention being to obtain great sensitiveness in the lamp and steadiness in the light, together with great simplicity in the construction of the said lamp and non-liability to derangement of the parts.

In carrying my invention into effect the lower carbon is supported by an arm secured to the lower ends of a pair of depending iron tubes magnetically insulated, preferably by a coating of brass. The upper carbon is carried by a soft-iron rod, which is arranged in the axis of a solenoid of copper wire, through which solenoid the primary current passes. Around the said solenoid is a secondary coil of fine wire. The said solenoid and secondary coil or shunt differ in no essential respect from like parts in electrical-arc lamps of the kind known as Brush lamps. The said coils are preferably of about eighteen inches in length. At the bottom of the soft-iron rod or core sliding in the axis of the solenoid is a short cross-arm of iron at right angles to the said soft-iron rod, which crossarm carries the upper carbon. The terminals of the primary current are connected, respectively, to the lower and upper carbons in the following manner: The positive pole of the primary current is connected to the upper end of the solenoid and after passing'through the solenoid traverses a flexible Wire electrically connected with the holder of the upper carbon. The negative pole of the primary current is electrically connected with the holder of the lower carbon. When the ends of the two carbons are brought into contact, the primary current passing through them and the solenoid draws the soft-iron rod or core into the axis of the solenoid, thereby separating the two carbon -points, the are passing between the said points. The separation of the carbon-points effects a certain resistance to the primary current, and the ascent of the core in the solenoid is arrested when there is a balance between the resistance of the arc to the passage of the primary current. The arm described carrying the upper carbon is guided in the up-and-down motion of the core by the depending brass rods or tubes which carry the arm supporting the lower carbon.

Figures 1 and 2 of the accompanying drawings represent elevations at right angles to one another of an arc-lamp containing my improvements. Fig. 3 is a plan of the top of the same. Fig. 4: represents the essential parts of the lamp, partly in elevation and partly in vertical section, drawn to a larger scale than Figs. 1, 2, and 3.

The same letters of reference indicate the same parts in the several figures of the drawlngs.

' dis the top supporting-plate of the lamp, to which is attached the hook a by which the lamp is suspended. The plate a may be of any suitable shape to receive the globe of the lamp. The top plate a is connected by de= pending tubular iron rods 1) b (insulated magnetically by a coating of brass) with an arm 0. The lower carbon at is secured in a tubular holder 6, attached to but insulated from the arm 0, and the electrical conductor fis passed or threaded through one of the arms 6 and is attached to the screw by which the carbon-holder e is secured to the arm a. The upper carbon g is secured in a holder carried by a cross-arm h, with forked ends which engage with the depending rods 1) b. The said cross-arm is secured to the lower end of a soft-iron rod 7:, which occupies the tubular axis of the solenoid 7c. The solenoid it, through which the primary electric current passes, is provided with the usual secondary or shunt coil of fine wire Z on its exterior. The lower end of the primary coil or solenoid 7c is' connected by a flexible conductor m with the binding-screw of the up per holder 19. v

r s are the binding-screws of the plate a, by which the conductors of the lamp are electrically connected with the main conductor. When the current is not passing, the end of the upper. carbon g rests on the end of the lower carbon d, as in Fig. 1. When the current is switched on, the action of the solenoid causes the soft'iron rod 2' to be drawn into the said solenoid, and thereby to effect the separation of the carbon-points, whereby the are is formed, the ascent of the soft'iron rod '2' in the solenoid 7tbeingarrested when there is a balance between the resistance of the are to the passage of the primary current.

lhe shunt or secondary coil is arranged in the ordinary way, so that when the main circuit is broken the magnetism will be reduced in the main coil and the shunt'coil will also be broken.

By the engagement of the forked ends of the cross-arm 72. with the depending" rods Z) l) the upper carbon 1 is guided in its up-and down motion.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is-- In an electric-arc lamp, an upper plate carrying a solenoid and shunt-coil, tubular rods depending from said plate, a lower plate connected to the lower ends of said rods, a cross-arm having its ends bifurcated and straddling said rods, a soft-iron rod electrically eonnected with the shunteoil its lower end being threaded and extending centrally through said crossarm, a second carbonholcler, having a threaded shank, a Washer carried by the lower plate to receive said shank and of insulating material, a conductor passing entirely through one of said tubular rods and connected with said threaded shank, and a nut on the latter.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

W'ILLIAM EDNVARD SYMONS.

Witnesses:

W. E. HEARD, P. CHAS. CESSAC. 

